In general, an automatic transmission includes, for example, a parking mechanism for causing a vehicle to be in a parking state and a manual valve for setting a range of a hydraulic control device, and can set a desired range such as parking (P), reverse (R), neutral (N), and drive (D) by a user's operation of a shift lever.
In a proposed conventional automatic transmission, an assist lever is coupled to a lower end of a manual shaft that is rotated by an operation of a shift lever so that rotation of the assist lever causes an axial position of a manual valve to change through a valve driving shaft (see Patent Document 1). The automatic transmission is configured in such a manner that a parking rod rotates in conjunction with the manual shaft so that the parking gear is locked.
In another proposed automatic transmission, a lever is interposed between an arm configured to rotate integrally with a detent plate by an operation of a shift lever and a parking rod, and a long hole is formed in the lever to have a shape allowing an engaging pawl provided at a distal end of a parking pawl and a parking gear to be engaged with each other when the shift lever is set in a P range (see Patent Document 2).